Striking clock



AWT 28), 11936. P. A. STEPHENSON M8355 STRIKNG CLOCK Filed Aug. 8, 1952 l 2 Sheets-Sheet l IN VEN TOR.

Patented Apr. 28, 1936 UNITED STATES PATENT OFFICE STRIKIN G CLOCK Application August 8, 1932, Serial No. 627,920

15 Claims.

My invention relates to striking clocks and has for its object the production of a clock striking mechanism in which the striking mechanism is put into operative condition at the proper time as well as actuated by the same means that operates the time indicating means or clock hands.

Its further object is the production of a clock striking mechanism for electric clocks that are actuated by means of synchronous motors.

Its further object is the production of an electric clock striking mechanism that is extremely simple and inexpensive in construction as well as positive and accurate in operation.

I accomplish these results by the means shown in the accompanying drawings, in which:

Fig. 1 is a front view of my striking mechanism which shows the parts in position as they are when the clock striking mechanism is not in the striking position.

Fig. 2 is a front view showing the mechanism in the warning position just before the minute hand comes to the exact time for striking.

Fig. 3 is a front view which shows the mechanism in position as the striking arm begins its striking operation. The striking arm is shown displaced from its normal position as indicated by the dotted line.

Fig. 4 is a View of the star wheel and hammer lift arm when the lift arm lies in the plane of 30 the teeth of the star wheel ready for the striking operation, the front plate being partly cut away.

Similar parts through the several Views are shown by the same numerals.

In the drawings the usual movement plates are indicated by means of the large circle shown. These plates contain the usual power driven train indicated in Figure 4 which in this electric clock is driven by means of a synchronous motor, not shown. The synchronous motor is suitably geared to this train so that the usual center shaft, shown, which carries the usual minute hand makes one rotation per hour as is usual in clocks. Fastened on the center shaft in front of the front plate is a two lobed center cam I and in front of the said cam and fastened to the usual hour wheel, not shown mounted on this same shaft is the snail 2. Cam I has two lobes, as shown, one longer than the other, the longer lobe raising the mechanism to free the rack 3 50 for the hour strike while the shorter lobes frees the rack 3 partly for the half hour strike. The snail 2 which is driven at the rate of one twelfth revolution per hour has twelve equal steps as shown, and determines the number of times the 55 clock will strike.

Rack 3 is pivotally mounted on a pin 29 fastened in the front plate and has a projection which lies in the plane of the steps on the snail 2 so that when said rack 3 is released from the pin 9 on the star wheel spring shift arm 8 the 5 projection 30 will engage the steps on the snail as shown in Figure 2. This arm 8 is pivotally mounted on a pin 6 fastened to a bent lever 4 which lever 4 is pivotally mounted to the front plate by means of a pin 5 on said front plate. :10 Lever 4 has a projection 3| that engages the lobes of center cam I by means of which said lever is actuated to put the striking mechanism into operative relation. Lever 4 has a spring 21 by means of which the projection 3| is held 15 against the surface of the lobes of center cam I and by means of which lever 4 is moved from the position shown in Figure 2 to that shown in Figure 1. Lever 4 further has a pin I mounted on it which engages the arm 8 making the two parts 4 and 8 act asv a unit, the arm 8 being held against the pin 1 on said lever 4 by means of the spring 28, shown. Figure 2 shows the rack 3 released as above described and in proper position to strike the correct hour with the projection 3l just ready to drop over the longer lobe of the center cam I to start the striking mechanism into operation as soon as the projection 3l drops over the edge of the said lobe, as shown in Figure 3. When said projection 3l drops over the lobe the pin 9 on arm 8 will immediately drop into the proper space between the teeth on rack 3. When said projection 3| is on the outer point of said lobe the pin 'I on lever 4 will have raised up the left hand end of arm 8 and forced down the right end of said arm towards the center shaft so that the cam surface I0 on said arm 8 will begin to engage the angular sliding surface I2 forming a separated part apart from the main body of the resilient star wheel shifting spring or member II by virtue of the slot I3, which member II has the further projections shown by means of which it is fastened on its opposite end to the front plate as shown. Spring member II has a slotted part 33 into which is rotatably fitted a collet I4 having a suitable groove into which the side parts of the slot 33 are retained so that the collet I4 is positioned by means of said spring member. Said collet I4 is fastened to the star wheel shaft 22 which is slidably and rotatably mounted in the movement plates. Mounted on said shaft 22 is the star wheel 23 and, it is evident, that the sidewise position of star wheel 23 is determined by said spring member II. When said starwheel 23 is thus held in its position nearest the front plate as just described the star wheel lies in the plane of the hammer lift arm 24 which is mounted on the hammer shaft 2| journaled in the movement plates which arm 24 then engages the teeth of the star wheel 23 which actuates the usual striking hammer, not shown. Mounted on the front end of said hammer shaft 2I is the gathering arm fulcrum and hammer stop I9 whose leftwise motion one way is limited by means of a pin 20 fastened in the front plate and whose rightwise motion is determined by the engagement of hammer lift arm 24 with the teeth of the wheel 23. Pivotally connected with said arm I9 by means of a pin I8 is the gathering lever I5 which has a projection I6 that gathers or engages the teeth 32 of the rack 3 and another projection II that engages the lever 4 and which removes the projection I6 from the teeth 32 of the rack 3 and thus allows rack 3 to freely move to the position shown in Figure 2 just previously to striking the time. It is evident that as the gathering arm I5 is reciprocated each time as 24 passes over one tooth of star wheel 23 that the projection I6 gathers up one tooth 32 on the rack 3 which rack 3 is held stationary after being thus moved by means of the pin 9 engaging the space between said teeth and when the proper required number of hammer strokes for the hour has thus been made the rack 3 which was previously properly positioned by the snail 2 will be pulled and rotated in the clockwise direction until the pin 9 slides downwardly on the left hand side of the rack 3, as shown in Figure 1, at which time also the cam I0 on arm 8 releases the angular part I2 of resilient member II so that the teeth of the star wheel 23 are again forced out of the plane of the hammer lift arm 24 until the next striking period when the above operations will be repeated.

It will be evident that the resilient member II being associated with the star wheel 23 and the hammer lift arm 24 as above described that all danger of binding or injuring of the teeth of the star wheel 23 or the point oi. the hammer lift arm 24 is avoided.

The shape of the cam I0 on the end of arm 8 is such that it has a level part immediately adjacent to the usual slanting or raising part, so that the different amounts of motion given to the lever 4 by the different lengths of the lobes on cam I will cause only the same sidewise movement of the star wheel 23 and also as well as not in anywise cause any undue friction of the movement of arm 8 as the pin 9 moves over the teeth 32 on the rack 3 as it does during the striking operation. It is evident that because of this feature this mechanism can be used to produce motion, if it is desired, where delayed timing action is needed for it is evident that the resilient member I I will be tensioned just the same even though a tooth of the star wheel 23 is thereby pushed against the lift arm 24 and temporarily held thereby as said star wheel will (because of the tensioning of said member II) spring into the plane of the lift arm 24 as soon as the tooth of star wheel 23 rotates off of the lift arm 24.

It will be seen that said arm 8 while it is actually pivotally mounted on lever 4 by means of the pin 6 that it can rotate in relation to said lever 4, also rotates with lever 4 around its pin 5 when the position of said arm 8 is such that said arm 8 is held against the pin 1 on lever 4 by means of the spring 28 shown, all as shown in Figures 1 and 2, while it turns around its pin 8 as a center when pin El rests in the tooth spaces and while cam IIJ shifts wheel 23 into engagement with 24 preparatory to the striking operation, as shown in Figure 3 during which time it holds out the member II to keep the teeth of the star wheel 23 in engagement with the hammer lift arm.

It is evident that the longer lobe on cam I will completely clear the rack 3 so that the hours will be properly sounded while the shorter lobe on the cam I will only partly clear the rack 3 for the half hour strike.

It will be understood, of course, that while I have here shown one form of my invention that I do not wish to limit myself to the -exact form shown but desire to have it taken in a sense illustrative of any and all the forms that fairly come Within the scope of the appended claims.

I claim:

l. In a striking clock, a driving means in combination with time indicating means, a rotatably and slida-biy mounted star wheel and a hammer moving means associated with said driving means, a cam and a snail associated with said time indicating means, a rack held in operative position by said snail, a gathering arm connected to and actuated by said hammer moving means co-acting with said rack, resilient means for retaining said star wheel out of operative relation with said hammer and intermediate mechanism co-acting with said cam and said resilient means to position said star wheel into operative relation with said hammer moving means.

2. In a striking clock, a driving means comprising a synchronous motor driven from a commercial lighting system in combination with time indicating means, a rotatably and slidably mounted star wheel and a hammer moving means associated with said driving means, a cam and a snail associated with means, a rack held in operative position by said snail, a gathering arm connected to and actuated by said hammer moving means co-acting with said rack, resilient means for retaining said star wheel out of operative relation with said hammer and intermediate mechanism co-acting with said cam and said resilient means to position said star wheel into operative relation with said hammer moving means.

3. In a striking clock, a driving means in com- 'r bination with time indicating means, a cam and a snail associated with said time indicating means, a rack co-acting with said snail, a pivotally mounted lever actuated by said cam, a star wheel driven by said driving means, a hammer actuat- A* ing means, mechanism for bringing said star wheel and said hammer actuating means into operative engagement, an arm plvotally mounted on said lever and means on said arm co-acting with said rack and said mechanism to bring said star wheel and said hammer actuating means into operative position.

4, In a striking clock, a driving means in combination with time indicating means, a cam and a snail associated with said time indicating means, a rack co-acting with said snail, a pivotally mounted lever actuated vby said cam, a star wheel driven by said driving means, a hammer actuating means, mechanism or bringing said star wheel and said hammer actuating means into operative engagement, an arm pivotally mounted on said lever with means on said arm co-actng with said rack and said mechanism to bring said star wheel and said hammer actuating means into operative position and means actuated by said said time indicating A hammer actuating means to move said rack during the striking period. v

5. In a striking clock, a driving means in combination with time indicating means, a rotatably and slidably mounted star wheel driven by said driving means, a hammer actuating means, positioning means to bring said star wheel to co-act with said hammer actuating means, a cam and a snail associated with said time indicating means, a rack co-acting with said snail, a pivotally mounted lever positioned by said cam, an arm pivotally mounted on said lever and means on said arm co-acting with said rack and said positioning means. v

6. In a striking clock, a driving means in combination with time indicating means, a star wheel driven by said driving means, a hammer actuating means, positioning means to bring said star Wheel and said hammer actuating means into operative relation, a cam and a snail associated with said time indicating means, a rack co-acting with said snail, a pivotally mounted lever positioned by said cam, an arm pivotally mounted on said lever and means on said arm co-acting with said rack, said lever and said positioning means whereby said positioning means is actuated.

7. In a striking clock, a driving means in combination with time indicating means, a rotatably and slidably mounted star Wheel and a hammer associated with said driving means, a gathering lever, a rack co-acting with said hammer by means of said gathering lever, a cam and a snail associated with said time indicating means, said snail co-acting with said rack, resilient means for retaining said star wheel out of operative relation with said hammer and intermediate mechanism co-acting with said cam and said resilient means to cause said resilient means to position said star wheel into operative relation with said hammer.

8. In a striking clock, a driving means comprising a synchronous motor driven from a commercial lighting system in combination With time indicating means, a rotatably and slidably mounted star wheel and a hammer associated with said driving means, a gathering lever, a rack co-acting with said hammer by means of said gathering lever, a cam and a snail associated with said time indicating means, said snail co-acting with said rack, resilient means for retaining said star wheel out of operative relation with said hammer and intermediate mechanism co-acting with said cam and said resilient means to cause said resilient means to position said star wheel into operative relation with said hammer.

9. In a striking clock, a driving means in combination with time indicating means, a rotatably and slidably mounted star wheel and a hammer associated with said driving means, a gathering lever, a rack co-acting with said hammer by means of said gathering lever, a cam and a snail associated with said time indicating means, said snail co-acting with said rack, resilient means for retaining said star wheel out of operative relation v/ith said hammer and intermediate mechanism Co-acting with said cam and said resilient means to position said star wheel into operative relation with said hammer, said mechanism comprising a lever pivotally mounted adjacent to said cam and an arm pivotally mounted on said lever having a projection that engages said resilient means.

l0. In a striking clock, a driving means comprising a synchronous motor driven from a commercial lighting system in combination with time indicating means, a rotatably and slidably mounted star Wheel and a hammer associated with said driving means, a gathering lever, a rack co-acting ,with said hammer by means of said gathering lever, a cam and a snail associated with said time indicating means, said snail co-acting with said rack, resilient means for retaining said star wheel out of operative. relation with said hammer and intermediate mechanism co-acting With said cam and said resilient means to position said star Wheel into operative relation with said hammer, said mechanism comprising a lever pivotally mounted adjacent to said cam and an arm pivotally mounted on said lever having a projection that engages said resilient means.

11. In a striking clock, a driving means in combination with time indicating means, a rotatably and slidably mounted star wheel and a hammer associated with said driving means, a gathering lever, a rack co-acting with said hammer by means of said gathering lever, a cam and a snail associated with said time indicating means, said snail co-acting with said rack, resilient means for retaining said star wheel out of operative relation With said hammer and intermediate mechanism co-a-cting with said cam and said resilient means to position said star Wheel into operative relation with said hammer, said resilient means comprising a plurality of associated yielding parts that permit delayed action between said star wheel, said intermediate mechanism and said hammer.

12. In a striking clock, a driving means comprising a synchronous motor driven from a commercial lighting system in combination with time indicating means, a rotatably and slidably mounted star wheel and a hammer associated with said driving means, a gathering lever, a rack co-acting with said hammer by means of said gathering lever, a cam and a snail associated with said time indicating means, said snail coacting with said rack, resilient means for retaining said star wheel out of operative relation with said hammer and intermediate mechanism coacting with said cam and said resilient means to position said star wheel into operative relation with said hammer, said resilient means comprising a plurality of associated yielding parts that permit delayed action between said star Wheel, said intermediate mechanism and said hammer.

13. In a striking clock, a driving means in combination with time indicating means, a rotatably and slidably mounted star wheel and a hammer associated with said driving means, a gathering lever, a rack co-acting with said hammer by means of said gathering lever, a cam and a snail co-acting With said rack, resilient means for positioning said star wheel in operative relation with said hammer and intermediate mechanism co-acting with said cam and said resilient means to retain said star wheel out of operative relation with said hammer.

14. In a striking clock, a synchronous motor driven from a commercial lighting system in combination with time indicating means, a star wheel and a hammer associated with said driving means, a gathering lever, a rack co-acting with said hammer by means of said gathering lever, a cam and a snail `co-acting with said time indicating mechanism, said snail co-acting with said rack, resilient means for retaining said star Wheel out of operative relation with said hammer and intermediate mechanism co-acting with said cam and said resilient means to position said star wheel into operative vrelation with said hammer. 15. In a stn'king clock, a driving means in combination with time indicating means, a star wheel and a, hammer associated with said driving 5 means, a gathering lever, a rack co-acting with said hammer by means of said gathering lever, a cam and a snail associated with said time indieating means, said snail co-acting with said rack, resilient means for retaining said star wheel out of operative relation with said hammer and intermediate mechanism 1o-acting with said cam and said resilient means to position said star 5 Wheel into operative relation with said hammer.

PAUL A. STEPHENSON. 

